This disclosure relates generally to insect repellent systems.
Insect repellents and related systems are employed in areas where mosquitoes, ticks, flies, etc. are prevalent or exist in high concentration. Although many insects are generally viewed as pests which may produce painful and/or itchy bites to humans and animals, these insects are also known to carry and transmit vector-borne infectious diseases. Vectors are living organisms that can transmit infectious diseases between humans or from animals to humans. Many of these vectors are bloodsucking insects, which ingest disease-producing microorganisms during a blood meal from an infected host (human or animal) and later inject it into a new host during their subsequent blood meal. Mosquitoes are the best known disease vector. Other vectors include ticks, flies, sandflies, fleas, triatomine bugs and some freshwater aquatic snails. Examples of vectors and diseases they transmit are listed below.
Mosquitoes                Aedes                     Dengue fever            Rift Valley fever            Yellow fever            Chikungunya                        Anopheles                     Malaria                        Culex                     Japanese encephalitis            Lymphatic filariasis            West Nile fever                        
Sandflies                Leishmaniasis        Sandfly fever (phelebotomus fever)        
Ticks                Crimean-Congo haemorrhagic fever        Lyme disease        Relapsing fever (borreliosis)        Rickettsial diseases (spotted fever and Q fever)        Tick-borne encephalitis        Tularaemia        
Triatomine bugs                Chagas disease (American trypanosomiasis)        
Tsetse flies                Sleeping sickness (African trypanosomiasis)        
Fleas                Plague (transmitted by fleas from rats to humans)        Rickettsiosis        
Black flies                Onchocerciasis (river blindness)        
Bed Bugs                Cimex lectularius                     Allergic reactions to their bites, which can be severe. Effects ranging from no reaction to a small bite mark to, in rare cases, anaphylaxis (severe, whole-body reaction)            Secondary infections of the skin from the bite reaction, such as impetigo, ecthyma, and lymphangitis            Mental health impacts on people living in infested homes. Reported effects include anxiety, insomnia and systemic reactions.                        
Vector-borne diseases are illnesses caused by pathogens and parasites in human populations. Every year there are more than 1 billion cases and over 1 million deaths from vector-borne diseases such as malaria, dengue, schistosomiasis, human African trypanosomiasis, leishmaniasis, Chagas disease, yellow fever, Japanese encephalitis and onchocerciasis, globally. Vector-borne diseases account for over 17% of all infectious diseases. Distribution of these diseases is determined by a complex dynamic of environmental and social factors. Globalization of travel and trade, unplanned urbanization and environmental challenges such as climate change are having a significant impact on disease transmission in recent years. Some diseases, such as dengue, chikungunya and West Nile virus, are emerging in countries where they were previously unknown.
The World Health Organization (WHO), for example, responds to vector-borne diseases in many ways, including                providing the best evidence for controlling vectors and protecting people against infection;        providing technical support and guidance to countries so that they can effectively manage cases and outbreaks;        supporting countries to improve their reporting systems and capture the true burden of the disease;        providing training on clinical management, diagnosis and vector control with some of its collaborating centers throughout the world; and        developing new tools to combat the vectors and deal with the disease, for example insecticide products and spraying technologies.        
An important element in addressing vector-borne diseases is behavioral change. The WHO currently works with partners to provide education and improve awareness so that people know how to protect themselves and their communities from mosquitoes, ticks, bugs, flies and other vectors. For many diseases such as Chagas disease, malaria, schistosomiasis and leishmaniasis, WHO has initiated control programs using donated or subsidized medicines. Access to water and sanitation is a very important factor in disease control and elimination. WHO works together with many different government sectors to control these diseases.
Along with being annoying pests which result in potentially painful and itchy bug bites, insects worldwide are responsible for                Vector-borne diseases account for more than 17% of all infectious diseases, causing more than 1 million deaths annually.        More than 2.5 billion people in over 100 countries are at risk of contracting dengue alone.        Malaria causes more than 600,000 deaths every year globally, most of them children under 5 years of age.        Other diseases such as Chagas disease, leishmaniasis and schistosomiasis affect hundreds of millions of people worldwide.        Many of these diseases are preventable through informed protective measures.        
Changes in agricultural practices due to variation in temperature and rainfall can affect the transmission of vector-borne diseases. Climate information can be used to monitor and predict distribution and longer-term trends in malaria and other climate-sensitive diseases. (Source: WHO March, 2014).
Known insect repellent systems have largely been unsatisfactory.